1. Field of the Invention
The present invention relates to a manufacture of a highly efficient catalyst carrier or a gas adsorbing element having a honeycomb structure and high efficiency. The catalyst carrier or gas adsorbing element has an extremely large surface area per unit volume, has high physical strength, has no danger of separating or scattering catalyst or gas adsorbent particles during use, and has a large amount of uniformly fixed catalyst or gas adsorbent per unit volume.
2. Description of the Prior Art
It was described in Japanese Patent Publication No. 15028/1984 that a catalyst carrier is obtained by preparing paper by adding a small amount of organic fiber and binder to ceramic fiber, by laminating the papers to form a honeycomb structure, by impregnating the paper or the honeycomb laminate with colloidal silica or ethyl silicate, converting the silicon compound to silica gel to increase paper strength, especially wet strength, and then by baking the formed structure to burn and remove organic fiber and organic binder in the paper.
When impregnating the catalyst carrier obtained in the above method with a catalyst powder such as titania and zeolite in sol form and in fixing it to the catalyst carrier, it is necessary to first impregnate the laminate with silica sol, etc., and to dry it to increase the wet strength of the paper and the formed structure and to prevent distortion of the laminate at the time of impregnation. However, in such a reinforcing process minute silica gel particles having a diameter of approximately 20 m.mu. are already fixed to internal fiber gaps of the paper. Therefore, during a second impregnation of the paper with a dispersion of large catalyst particles having a particle diameter of several .mu., it is extremely difficult for catalyst particles to permeate into fiber gaps of the paper. In addition, most of the catalyst particles remain adhered to the paper surface. Therefore, it is difficult to make a catalyst carrier carry a large quantity of catalyst and at the same time the defect of occurrence of catalyst particle separation and carrying-over by the flow of process fluid while in use cannot be avoided. This is the same in a case of obtaining a gas adsorbing element by impregnating a similar honeycomb laminate with gas adsorbent and fixing the gas adsorbent to the honeycomb laminate.